CVE-2018-21248
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of...
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.
- Record
CVE-2018-21248- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:P/I:N/A:N - Weakness
- CWE-522
- Updated
- 2026-11-02
CVE List No score
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.
- Record
CVE-2018-21248- Updated
- 2026-11-02
EUVDEUVD-2018-13763 No score
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.
- Record
EUVD-2018-13763- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-xppr-f495-xp3j No score
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of...
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.
- Record
GHSA-xppr-f495-xp3j- Updated
- 2026-11-02
OSV
An issue was discovered in Mattermost Server before 5.4.0. It mishandles possession of superfluous authentication credentials.
- Record
CVE-2018-21248- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-21248 is a high vulnerability (CVSS 7.5) in Mattermost Server, published June 19, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.23%, the 69th percentile. No source names a fixed version.